In the art of detergency, formulators have used enzymes in detergent compositions for a variety of fabric laundering purposes, including removal of protein-based, carbohydrate-based, or triglyceride-based stains, and for the prevention of refugee dye transfer, and for fabric restoration. Typically, enzymes such as protease, amylases, lipases, cellulases and peroxidases have been used for such purposes. One major drawback to the use of enzymes in detergents is the unpleasant odor contribution such enzymes and the feedstocks in which the enzymes are usually contained and delivered. These enzymes and their feedstocks are complex mixtures obtained from fermentation processes and they typically contain many offensive odor contaminants which ultimately find their way into the detergent products in which the enzymes are included. The resulting malodors in such detergent compositions does not appeal to consumers. Additionally, the detergency enzymes have a tendency to leave residual odors on the fabric itself which leads to consumer dissatisfaction, as well.
In the past, these drawbacks have often been countered by limiting the level of enzyme used in the composition. However, this approach restricts product efficacy and does not entirely eliminate the malodor problem. Another approach entails "purifying" the enzyme so as to reduce the amount of malodor constituents in the enzyme itself prior to incorporation into the detergent. More particularly, detergent compositions containing protease enzyme have been purified such that they do not have a detectable odor in distilled water at specified concentration levels. While this approach provides a viable option, it requires an additional step in the manufacture of the detergent (i.e. the purifying step), thereby resulting in a more expensive product.
Other attempts in the art have also only focused on especially problematic enzymes. By way of example, there have been attempts directed to counteracting malodors associated with fabrics laundered with detergent compositions containing lipases. Enzymes such as lipases and protease have been known to exhibit offensive odors as contained in the detergent as well as to cause residual malodors on fabrics laundered with such protease or lipase-containing detergents. In that regard, certain perfumes have been used to mask the residual odors on fabrics caused by the lipase-containing detergents.
As is known, cellulase enzymes have been used in the art of detergency for purposes of providing fabric care as well as cleaning performance. It has also been known that perfumes may be included in cellulase-containing detergents. However, there is still a need for a detergent composition containing specific perfumes especially suitable for counteracting malodors associated with cellulase enzyme and its feedstock as well as the residual malodors which may be found on fabrics laundered with such cellulase-containing detergents. Moreover, it would be desirable to have a means by which the compatibility of the cellulase enzyme and perfume can be improved so as to provide a more stable detergent.
Accordingly, there remains a need for a cellulase-containing detergent composition which does not itself exhibit malodors or cause fabrics laundered such a composition to have residual malodors. There is also a need in the art for such a cellulase-containing detergent composition which exhibits improved stability.